U.S. patent application number 16/613816 was filed with the patent office on 2020-08-27 for self-moving apparatus and method for controlling same.
The applicant listed for this patent is Positec Power Tools (Suzhou) Co., Ltd. Invention is credited to Jiang DU, Yuanzhong RAN, Kai WANG.
Application Number | 20200272165 16/613816 |
Document ID | / |
Family ID | 1000004841283 |
Filed Date | 2020-08-27 |
View All Diagrams
United States Patent
Application |
20200272165 |
Kind Code |
A1 |
RAN; Yuanzhong ; et
al. |
August 27, 2020 |
SELF-MOVING APPARATUS AND METHOD FOR CONTROLLING SAME
Abstract
Embodiments of the present invention relates to a self-moving
apparatus and a method for controlling same, the self-moving
apparatus including: a housing; a movement module for driving the
housing to move; an ultrasonic module configured to transmit an
ultrasonic signal and receive an echo signal formed through
reflection of an obstacle; and a control module installed on the
housing and connected to the ultrasonic module, to implement an
ultrasonic detection function by processing the echo signal,
thereby controlling a movement mode of the movement module. The
control module can control disabling of the ultrasonic detection
function according to a received preset signal.
Inventors: |
RAN; Yuanzhong; (Jiangsu,
CN) ; DU; Jiang; (Jiangsu, CN) ; WANG;
Kai; (Jiangsu, CN) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Positec Power Tools (Suzhou) Co., Ltd |
Suzhou |
|
CN |
|
|
Family ID: |
1000004841283 |
Appl. No.: |
16/613816 |
Filed: |
November 14, 2018 |
PCT Filed: |
November 14, 2018 |
PCT NO: |
PCT/CN2018/115436 |
371 Date: |
November 15, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
G05D 1/0061 20130101;
G05D 1/0255 20130101; G05D 1/0022 20130101; G05D 1/0238 20130101;
G05D 2201/0208 20130101 |
International
Class: |
G05D 1/02 20060101
G05D001/02; G05D 1/00 20060101 G05D001/00 |
Foreign Application Data
Date |
Code |
Application Number |
Nov 14, 2017 |
CN |
201711123631.2 |
Apr 20, 2018 |
CN |
201810362322.9 |
Apr 20, 2018 |
CN |
201810362730.4 |
Claims
1. A self-moving apparatus, comprising: a housing; a movement
module installed on the housing for driving the housing to move; an
ultrasonic module installed on the housing for transmitting an
ultrasonic signal and receiving an echo signal formed through
reflection of an obstacle; and a control module installed on the
housing and connected to the ultrasonic module, to implement an
ultrasonic detection function by processing the echo signal,
thereby controlling a movement mode of the movement module; wherein
the control module can control disabling of the ultrasonic
detection according to a received preset signal.
2. The self-moving apparatus according to claim 1, wherein the
preset signal comprises a manual control signal.
3. The self-moving apparatus according to claim 2, wherein the
manual control signal is generated by a user operation.
4. The self-moving apparatus according to claim 2, wherein the
self-moving apparatus comprises a communication module connected to
the control module, the communication module receiving the manual
control signal sent by a terminal.
5. The self-moving apparatus according to claim 2, wherein the
self-moving apparatus comprises an operating module connected to
the control module, the manual control signal being generated by
the operating module.
6. The self-moving apparatus according to claim 1, wherein the
preset signal comprises an abnormal signal.
7. The self-moving apparatus according to claim 6, wherein the
abnormal signal comprises a valid signal that satisfies a preset
condition.
8. The self-moving apparatus according to claim 7, wherein the
preset condition comprises that a time being greater than preset
time and/or a number being greater than a preset number.
9. The self-moving apparatus according to claim 7, wherein the
valid signal comprises an echo signal with strength greater than
preset strength.
10. The self-moving apparatus according to claim 6, wherein the
self-moving apparatus comprises an energy module connected to the
control module, the control module receiving an energy signal of
the energy module, and the abnormal signal comprising the energy
signal with energy less than preset energy.
11. The self-moving apparatus according to claim 1, wherein the
disabling of the ultrasonic detection function comprises stopping
operation of the ultrasonic module.
12. The self-moving apparatus according to claim 1, wherein the
disabling of the ultrasonic detection function comprises stopping
processing the echo signal by the control module.
13. The self-moving apparatus according to claim 1, wherein a
detection range of the ultrasonic module in a height direction is a
first height range, and the self-moving apparatus further comprises
an auxiliary detecting module configured to detect an obstacle
within a second height range.
14. The self-moving apparatus according to claim 13, wherein the
control module controls a movement mode of the movement module
according to an output signal of the ultrasonic module and/or the
auxiliary detecting module.
15. A method for controlling a self-moving apparatus, the
self-moving apparatus comprising a movement module, an ultrasonic
module, and a control module, the control module being connected to
the ultrasonic module to implement an ultrasonic detection
function, thereby controlling a movement mode of the movement
module; wherein the control method comprises: transmitting, by the
ultrasonic module, an ultrasonic signal and receiving an echo
signal formed through reflection of an obstacle; and controlling,
by the control module, disabling of the ultrasonic detection
function based on at least strength of the echo signal.
16. A method for controlling a self-moving apparatus, the
self-moving apparatus comprising a movement module, an ultrasonic
module, and a control module, the ultrasonic module transmitting an
ultrasonic signal and receiving an echo signal formed through
reflection of an obstacle, and the control module being connected
to the ultrasonic module to implement an ultrasonic detection
function, thereby controlling a movement mode of the movement
module; wherein the control method comprises: receiving, by the
control module, a preset signal; and controlling, by the control
module, disabling of the ultrasonic detection function based on at
least a preset signal.
Description
BACKGROUND
Technical Field
[0001] Embodiments of the present invention relates to a
self-moving apparatus and a method for controlling same.
Related Art
[0002] With the continuous improvement of computer technologies and
artificial intelligence technologies, a self-moving apparatuses
similar to an autonomous apparatus is gradually used in people's
life. Companies such as Samsung and Electrolux have developed a
fully automatic vacuum cleaner which has already entered the
market. Such fully automatic vacuum cleaner is usually small in
size and integrated with an environmental sensor, a self-driven
system, a dust extraction system, and a battery and charging
system, which can automatically cruise and vacuum within a working
area without manual control, automatically return to a charging
station to be connected and charged when being in low energy, and
then continue cruising and vacuuming. At the same time, companies
such as Husqvarna have developed a similar autonomous lawn mower
that can automatically mow the grass and be charged in a lawn of a
user without needing user's intervention. Because such self-moving
apparatus does not require further effort for management after
being set once, and the user is liberated from tedious,
time-consuming, and laborious housework such as cleaning and lawn
maintenance, such self-moving apparatus is greatly welcomed.
[0003] There are usually obstacles that hinder movement of the
self-moving apparatus within the working area. Therefore, the
self-moving apparatus is required to have a function for
recognizing the obstacles, so as to further automatically evade the
obstacle when encountering an obstacle or automatically bypass the
obstacle before encountering an obstacle.
[0004] In conventional technologies, a contact obstacle-avoidance
means is used on the self-moving apparatus. In the technologies, a
collision sensor is disposed on a body of the self-moving
apparatus. When the self-moving apparatus collides with an
obstacle, the collision sensor generates a collision signal, and a
control module of the self-moving apparatus receives the collision
signal, and determines that an obstacle exists in a direction in
which the self-moving apparatus moves forward, to further control
the self-moving apparatus to turn or move rearward for avoiding
obstacles
SUMMARY
[0005] In the contact obstacle-avoidance mode, the self-moving
apparatus can recognize the obstacle only when colliding with the
obstacle. Such mode not only requires high collision strength for
the body of the self-moving apparatus, but also still cannot be
adapted to some working conditions in which a collision is
unsuitable to occur, which increases production costs of the
self-moving apparatus. One aspect of the present invention is
intended to provide a self-moving apparatus that can implement
non-contact obstacle avoidance, and in particular, to provide a
self-moving apparatus that can operate stably and can implement
non-contact obstacle avoidance.
[0006] The technical solution used by embodiments of the present
invention to resolve the problem in the prior art is as
follows:
[0007] A self-moving apparatus, comprising: a housing; a movement
module installed on the housing for driving the housing to move; an
ultrasonic module installed on the housing for transmitting an
ultrasonic signal and receiving an echo signal formed through
reflection of an obstacle; and a control module installed on the
housing and connected to the ultrasonic module, to implement an
ultrasonic detection function by processing the echo signal,
thereby controlling a movement mode of the movement module; wherein
the control module can control disabling of the ultrasonic
detection function according to a received preset signal.
[0008] In one embodiment, the preset signal comprises a manual
control signal.
[0009] In one embodiment, the manual control signal is generated by
a user operation.
[0010] In one embodiment, the self-moving apparatus comprises a
communication module connected to the control module, the
communication module receiving the manual control signal sent by a
terminal.
[0011] In one embodiment, the self-moving apparatus comprises an
operating module connected to the control module, the manual
control signal being generated by the operating module.
[0012] In one embodiment, the preset signal comprises an abnormal
signal.
[0013] In one embodiment, the abnormal signal comprises a valid
signal that satisfies a preset condition.
[0014] In one embodiment, the preset condition comprises that a
time being greater than preset time and/or a number being greater
than a preset number.
[0015] In one embodiment, the valid signal comprises an echo signal
with strength greater than preset strength.
[0016] In one embodiment, the self-moving apparatus comprises an
energy module connected to the control module, the control module
receiving an energy signal of the energy module, and the abnormal
signal comprising the energy signal with energy less than preset
energy.
[0017] In one embodiment, the disabling of the ultrasonic detection
function comprises stopping operation of the ultrasonic module.
[0018] In one embodiment, the disabling of the ultrasonic detection
function comprises stopping processing the echo signal by the
control module.
[0019] In one embodiment, a detection range of the ultrasonic
module in a height direction is a first height range, and the
self-moving apparatus further comprises an auxiliary detecting
module configured to detect an obstacle within a second height
range.
[0020] In one embodiment, the control module controls a movement
mode of the movement module according to an output signal of the
ultrasonic module and/or the auxiliary detecting module.
[0021] A method for controlling a self-moving apparatus, the
self-moving apparatus comprising a movement module, an ultrasonic
module, and a control module, the control module being connected to
the ultrasonic module to implement an ultrasonic detection
function, thereby controlling a movement mode of the movement
module; wherein the control method comprises: transmitting, by the
ultrasonic module, an ultrasonic signal and receiving an echo
signal formed through reflection of an obstacle; and controlling,
by the control module, disabling of the ultrasonic detection
function based on at least strength of the echo signal.
[0022] A method for controlling a self-moving apparatus, the
self-moving apparatus comprising a movement module, an ultrasonic
module, and a control module, the ultrasonic module transmitting an
ultrasonic signal and receiving an echo signal formed through
reflection of an obstacle, and the control module being connected
to the ultrasonic module to implement an ultrasonic detection
function, thereby controlling a movement mode of the movement
module; wherein the control method comprises: receiving, by the
control module, a preset signal; and controlling, by the control
module, disabling of the ultrasonic detection function based on at
least a preset signal.
[0023] A method for controlling a self-moving apparatus is
provided. The self-moving apparatus includes a movement module, an
ultrasonic module, and a control module, the ultrasonic module
transmitting an ultrasonic signal and receiving an echo signal
formed through reflection of an obstacle, and the control module
being connected to the ultrasonic module to implement an ultrasonic
detection function, thereby controlling a movement mode of the
movement module; and the control method includes: receiving, by the
control module, a preset signal; and controlling, by the control
module, disabling of the ultrasonic detection function based on at
least the preset signal.
[0024] In some specific working scenarios (for example, in a
heavily rainy day, when a lawn height exceeds a normal value, when
an obstacle adheres to a probe surface, and when returning to a
charging station across a border line, etc.), if the ultrasonic
detection function is enabled, a machine will continuously detect
the obstacle and continually take obstacle avoidance measures such
as changing the movement mode. In such specific working scenarios,
controlling disabling of the ultrasonic detection function can
ensure normal operation of the machine.
[0025] In addition, if an ultrasonic probe is always in a working
state after an autonomous lawn mower is enabled, on the one hand,
power consumption is increased, and single life time becomes
shorter, and on the other hand, service life of the ultrasonic
probe is shortened. Controlling disabling of the ultrasonic
detection function through a signal such as residual energy can
reduce service time and energy consumption of the ultrasonic probe,
thereby prolonging the service life of the ultrasonic probe and
reducing the energy loss of the autonomous lawn mower.
[0026] A method for controlling an autonomous lawn mower is
provided in an embodiment of the present invention, the autonomous
lawn mower including a main control board and an ultrasonic probe,
and the main control board being connected to the ultrasonic
probe.
[0027] The method includes: [0028] receiving, by the main control
board, a control signal sent by a signal apparatus, the control
signal being used to indicate enabling or disabling of a detection
function of the ultrasonic probe; [0029] generating, by the main
control board according to the control signal, a switch signal for
controlling turn-on or turn-off of the ultrasonic probe; and [0030]
turning on or turning off, by the main control board, the
ultrasonic probe according to the switch signal.
[0031] In one of the embodiments, the signal apparatus includes any
of the following: [0032] a terminal wirelessly connected to the
main control board, the ultrasonic probe, an operating module, or
an energy module of the autonomous lawn mower.
[0033] In one embodiment, the signal apparatus is the ultrasonic
probe, and the control signal is an echo signal sent by the
ultrasonic probe. The receiving, by the main control board, a
control signal sent by a signal apparatus includes: [0034]
receiving, by the main control board, an echo signal formed through
reflection of the ultrasonic signal sent by the ultrasonic probe by
an obstacle; [0035] acquiring, by the main control board, a
distance between the autonomous lawn mower and the obstacle
according to the echo signal; and [0036] if the distance is less
than a preset distance, determining, by the main control board,
that the echo signal is used to indicate disabling of the detection
function of the ultrasonic probe.
[0037] In one of the embodiments, before the receiving, by the main
control board, an echo signal formed through reflection of the
ultrasonic signal sent by the ultrasonic probe by an obstacle, the
method further includes: [0038] acquiring, by the main control
board, a transmission time at which the ultrasonic probe transmits
an ultrasonic signal; and [0039] the acquiring, by the main control
board, a distance between the autonomous lawn mower and the
obstacle according to the echo signal includes: [0040] acquiring,
by the main control board, the distance between the autonomous lawn
mower and the obstacle according to the transmission time, a
receiving time of the echo signal, and a propagation speed of the
ultrasonic wave in the air.
[0041] In one of the embodiments, the autonomous lawn mower further
includes a temperature sensor connected to the main control board.
Before the acquiring, by the main control board, the distance
between the autonomous lawn mower and the obstacle according to the
transmission time, a receiving time of the echo signal, and a
propagation speed of the ultrasonic wave in the air, the method
further includes: [0042] acquiring, by the main control board, a
temperature parameter of a current environment monitored by the
temperature sensor; and [0043] determining, by the main control
board, a propagation speed of the ultrasonic wave in the air
according to the temperature parameter.
[0044] In one of the embodiments, the signal apparatus is the
ultrasonic probe, and the control signal is an ultrasonic signal
transmitted by the ultrasonic probe. The receiving, by the main
control board, a control signal sent by a signal apparatus
includes: [0045] acquiring, by the main control board, a
transmission time at which the ultrasonic probe transmits the
ultrasonic signal and starting a timer at the transmission time
point; and [0046] if the main control board does not receive the
echo signal sent by the ultrasonic probe after the timer times out,
determining, by the main control board, that the ultrasonic signal
is used to indicate disabling of the detection function of the
ultrasonic probe.
[0047] In one of the embodiments, after the receiving, by the main
control board, a control signal sent by a signal apparatus, the
method further includes: [0048] acquiring, by the main control
board, a turn-off time at which the ultrasonic probe is turned off;
[0049] determining, by the main control board, a restart time
according to the turn-off time, a maximum detection distance of the
ultrasonic probe, and a travelling speed of the autonomous lawn
mower; and [0050] turning on, by the main control board, the
ultrasonic probe within a preset time period before the restart
time according to the restart time.
[0051] In one of the embodiments, the signal apparatus is an energy
module of the autonomous lawn mower, and the control signal is a
low-energy signal sent by the energy module. The receiving, by the
main control board, a control signal sent by a signal apparatus
includes: [0052] acquiring, by the main control board, a low-energy
signal sent by the energy module, the low-energy signal being a
signal sent by the energy module when a current electric quantity
of the autonomous lawn mower is less than a preset electric
quantity; and [0053] determining, by the main control board
according to the low-energy signal, that the low-energy signal is
used to indicate disabling of the detection function of the
ultrasonic probe.
[0054] The foregoing main control board of the autonomous lawn
mower receives the control signal sent by the signal apparatus for
indicating enabling or disabling of the detection function of the
ultrasonic probe, generates, according to the control signal, the
switch signal for controlling turn-on or turn-off of the ultrasonic
probe, and turns on or turns off the ultrasonic probe according to
the switch signal. The signal apparatus includes the terminal
wirelessly connected to the main control board, the ultrasonic
probe, and the operating module or the energy module of the
autonomous lawn mower. The control signal sent by any of the
foregoing signal apparatuses can be used to control the working
state of the ultrasonic probe of the autonomous lawn mower, thereby
avoiding problems such as single-package duration being shortened
and the probe service life being shortened as a result of frequent
enabling of the ultrasonic obstacle-avoidance function, and
interference to normal working of the autonomous lawn mower in the
special working condition.
[0055] A method for controlling an autonomous lawn mower is further
provided in the embodiments of the present invention, the
autonomous lawn mower including an ultrasonic probe, and the method
includes: [0056] transmitting an ultrasonic signal through the
ultrasonic probe; [0057] receiving an echo signal through the
ultrasonic probe, the echo signal being formed through reflection
of the ultrasonic signal; and [0058] performing an avoiding
operation according to the ultrasonic signal and the echo signal,
and after that, if a number of valid signals in the echo signals
received within a preset time is greater than a preset threshold,
performing an action of terminating the avoiding operation, the
valid signal being used as an echo signal for the autonomous lawn
mower to perform the avoiding operation.
[0059] In one of the embodiments, the performing an action of
terminating the avoiding operation includes: [0060] disabling a
detection function of the ultrasonic probe.
[0061] In one of the embodiments, the performing an action of
terminating the avoiding operation includes: [0062] disabling a
walking system for enabling the autonomous lawn mower to move
forward, move backward, or turn in the autonomous lawn mower.
[0063] In one of the embodiments, the method further includes:
[0064] disabling a cutting system for cutting grass in the
autonomous lawn mower if a number of valid signals in the echo
signals received within a preset time is greater than a preset
threshold.
[0065] In one of the embodiments, the method further includes:
[0066] outputting alarm information through a speaker and/or an
indicator light if the number of the valid signals in the echo
signals received within a preset time is greater than the preset
threshold, the alarm information being used to indicate that the
autonomous lawn mower is abnormal.
[0067] In one of the embodiments, the method further includes:
[0068] sending prompt information to a terminal apparatus if the
number of the valid signals in the echo signals received within a
preset time is greater than the preset threshold, the prompt
information being used to indicate that the autonomous lawn mower
is abnormal, and the terminal apparatus being wirelessly connected
to the autonomous lawn mower.
[0069] An autonomous lawn mower is further provided in the
embodiments of the present invention, including: [0070] an
ultrasonic probe, a walking system, a cutting system, and a control
module of any of the foregoing autonomous lawn mowers.
[0071] A control module of an autonomous lawn mower is provided in
the embodiments of the present invention, including: [0072] a
receiving module configured to receive a control signal sent by a
signal apparatus, the control signal being used to indicate
enabling or disabling of a detection function of an ultrasonic
probe, and the signal apparatus including any of the following: a
terminal wirelessly connected to a main control board, the
ultrasonic probe, an operating module, or an energy module of the
autonomous lawn mower; [0073] a generating module configured to
generate, according to the control signal, a switch signal for
controlling turn-on or turn-off of the ultrasonic probe; and [0074]
an execution module configured to turn on or turn off the
ultrasonic probe according to the switch signal.
[0075] A control module of an autonomous lawn mower is provided in
the embodiments of the present invention, including: [0076] a
memory; a processor; and a computer program.
[0077] The computer program is stored in the memory and is
configured to perform the method in any of a first aspect by the
processor to control enabling or disabling of the detection
function of the ultrasound probe.
[0078] A computer-readable storage medium is provided in the
embodiments of the present invention, on which a computer program
is stored, the computer program being executed by the processor to
implement the method in any of the first aspect.
[0079] The autonomous lawn mower receives the echo signal formed
through reflection of the ultrasonic signal transmitted by the
ultrasonic probe, and determines, according to the transmitted
ultrasonic signal and the echo signal, whether to perform the
avoiding operation, so that the autonomous lawn mower can avoid an
obstacle effectively, and determines whether a number of valid
signals received within the preset time is greater than the preset
threshold. When the number of the valid signals is greater than the
preset threshold, the action of terminating the avoiding operation
is performed, thereby terminating unnecessary avoidance and
improving stability and reliability of the autonomous lawn mower
during working.
[0080] A method for avoiding an obstacle by a self-moving apparatus
is further provided in the embodiments of the present invention,
including: acquiring a first signal indicating that there is an
obstacle within a first height range; acquiring a second signal
indicating that there is an obstacle within a second height range;
issuing an obstacle avoidance instruction according to the first
signal and the second signal; and changing a walking path of the
self-moving apparatus according to the obstacle avoidance
instruction.
[0081] The foregoing method for avoiding an obstacle by the
self-moving apparatus may be used to detect obstacles within
different height ranges. When working in complex environments with
flowers, trunks, and bushes, the self-moving apparatus performs an
avoidance action using the obstacle avoidance method, which is more
intelligent to be adapted to a complex working environment, safety
of the self-moving apparatus is improved.
[0082] In one of the embodiments, the step of the acquiring a first
signal indicating that there is an obstacle within a first height
range specifically includes: transmitting an ultrasonic signal to a
surrounding environment; receiving a reflection signal of the
ultrasonic signal by the surrounding environment; determining,
according to the reflection signal, whether there is an obstacle
within the first height range.
[0083] In one of the embodiments, the step of the determining,
according to the reflection signal, whether there is an obstacle
within the first height range specifically includes: acquiring a
first preset parameter value indicating that there is an obstacle
within a first height range; when a first parameter value of the
reflection signal is greater than the first preset parameter value
indicating that there is the obstacle within the first height
range, determining that there is an obstacle within the first
height range.
[0084] In one of the embodiments, the first parameter value of the
reflection signal is a strength value of the reflection signal.
[0085] In one of the embodiments, the step of the acquiring a first
signal indicating that there is an obstacle within a first height
range further includes: converting, into a second parameter value
of the first signal, a time difference between a time at which an
ultrasonic wave is transmitted and a time at which the ultrasonic
wave is received, the second parameter value of the first signal
being used to represent a distance between the self-moving
apparatus and the obstacle within the first height range.
[0086] In one of the embodiments, the method further includes the
following steps: acquiring a second preset value of the first
signal; and when a first signal parameter value is less than the
second preset parameter value of the first signal, issuing an
obstacle avoidance instruction.
[0087] In one of the embodiments, the step of the acquiring a
second signal indicating that there is an obstacle within a second
height range specifically includes: acquiring a second signal
parameter value indicating that there is an obstacle within the
second height range after the self-moving apparatus collides with
an obstacle within the second height range.
[0088] In one of the embodiments, the method further includes the
following steps: acquiring a preset parameter value of the second
signal; and when a second signal parameter value is greater than
the preset parameter value of the second signal, issuing an
obstacle avoidance instruction.
[0089] In one of the embodiments, a minimum value of the first
height range is not greater than a maximum value of the second
height range.
[0090] A self-moving apparatus is further provided in the
embodiments of the present invention, including: a first detecting
module configured to acquire a first signal indicating that there
is an obstacle within a first height range; and a second detecting
module disposed below the first detecting module configured to
acquire a second signal indicating that there is an obstacle within
a second height range; [0091] a processing module configured to
issue an obstacle avoidance instruction according to the first
signal and the second signal; and [0092] a control module
configured to control a walking path of the self-moving apparatus
according to the obstacle avoidance instruction.
[0093] The foregoing self-moving apparatus may detect obstacles
within different height ranges. When working in complex
environments with flowers, trunks, and bushes, the self-moving
apparatus performs an avoidance action, which is more intelligent
to be adapted to a complex working environment, and safety of the
self-moving apparatus is improved.
[0094] In one of the embodiments, the first detecting module
includes an ultrasonic probe, the ultrasonic probe being configured
to transmit and receive an ultrasonic signal, the ultrasonic probe
being installed on a fixing base of the ultrasonic probe, and the
fixing base of the ultrasonic probe being disposed on a housing of
the self-moving apparatus.
[0095] In one of the embodiments, the second detecting module
includes a magnetic block and a Hall element for sensing the
magnetic block, the Hall element being configured to detect whether
the magnetic block is displaced, and the Hall element including at
least two Hall sensors.
[0096] A minimum value of a first height range is set to be not
greater than a maximum value of a second height range, and there is
no gap between the first height range and the second height range.
Then, the first height range and the second height range
substantially cover a height of an obstacle. The obstacle is
detected using characteristics of an ultrasonic wave within the
first height range covered by the ultrasonic wave. The obstacle is
detected through collision contact within the second height range
that cannot be covered by the ultrasonic wave. In this way,
obstacles within different height ranges may be detected using the
foregoing obstacle avoidance methods, and different obstacle
avoidance means may be further used.
BRIEF DESCRIPTION OF THE DRAWINGS
[0097] The foregoing objectives, technical solutions, and
beneficial effects of embodiments of the present invention may be
implemented by using the accompanying drawings below:
[0098] FIG. 1 is a schematic structural diagram of an autonomous
lawn mower according to an embodiment of the present invention;
[0099] FIG. 2 is a schematic diagram of some components of an
autonomous lawn mower according to an embodiment of the present
invention;
[0100] FIG. 3 is a schematic flowchart of a method for controlling
an autonomous lawn mower according to an embodiment of the present
invention;
[0101] FIG. 4 is a schematic flowchart of a method for controlling
an autonomous lawn mower according to an embodiment of the present
invention;
[0102] FIG. 5 is a schematic flowchart of a method for controlling
an autonomous lawn mower according to an embodiment of the present
invention;
[0103] FIG. 6 is a schematic flowchart of a method for controlling
an autonomous lawn mower according to an embodiment of the present
invention;
[0104] FIG. 7 is a schematic structural diagram of a control module
of an autonomous lawn mower according to an embodiment of the
present invention;
[0105] FIG. 8 is a schematic structural diagram of a control module
of an autonomous lawn mower according to an embodiment of the
present invention;
[0106] FIG. 9 is a flowchart of a method for controlling an
autonomous lawn mower according to an embodiment of the present
invention;
[0107] FIG. 10 is a flowchart of a method for controlling an
autonomous lawn mower according to an embodiment of the present
invention;
[0108] FIG. 11 is a schematic structural diagram of a control
module of an autonomous lawn mower according to an embodiment of
the present invention;
[0109] FIG. 12 is a flowchart of a method for avoiding an obstacle
by an autonomous lawn mower in an embodiment according to the
present invention;
[0110] FIG. 13 is a flowchart of a method for avoiding an obstacle
by an autonomous lawn mower in a preferred embodiment according to
the present invention;
[0111] FIG. 14 is a flowchart of a method for avoiding an obstacle
by an autonomous lawn mower in another preferred embodiment
according to the present invention;
[0112] FIG. 15 is a schematic diagram of an autonomous lawn mower
in an embodiment according to the present invention;
[0113] FIG. 16 is a schematic diagram of an autonomous lawn mower
in an embodiment according to the present invention;
[0114] FIG. 17 is a schematic diagram of an ultrasonic obstacle
avoidance component of an autonomous lawn mower in an embodiment
according to the present invention; and
[0115] FIG. 18 is a schematic diagram of an autonomous lawn mower
and a working scenario thereof in an embodiment according to the
present invention.
DETAILED DESCRIPTION
[0116] In the embodiments of the present invention, a self-moving
apparatus may be a similar autonomous apparatus such as an
autonomous lawn mower, an autonomous snowplow, an autonomous
cleaning apparatus, an autonomous scrubber, and the like that can
work automatically. The autonomous lawn mower is used as an example
herein.
[0117] An ultrasonic wave is characterized with a high frequency, a
short wavelength, and few diffraction phenomena, especially good
directivity, and a capability of becoming a ray for directional
propagation. The ultrasonic wave generates significant reflection
when encountering an impurity or an interface and forms an echo
wave, and can generate a Doppler effect when encountering a moving
object. In the embodiment of the present invention, the autonomous
lawn mower is equipped with an ultrasonic probe developed using
characteristics of the ultrasonic wave, the ultrasonic probe being
configured to measure a distance between the autonomous lawn mower
during working and an obstacle. When the distance between the
autonomous lawn mower and the obstacle is less than a preset value,
the autonomous lawn mower automatically performs an avoidance
action to avoid causing damage to the autonomous lawn mower and
even causing an accident as a result of a collision with the
obstacle.
[0118] FIG. 1 is a schematic structural diagram of an autonomous
lawn mower according to an embodiment of the present invention. As
shown in FIG. 1, an autonomous lawn mower 10 provided in this
embodiment includes a housing 400; a movement module 600 installed
on the housing 400 for driving the housing 400 to move; an
ultrasonic module 300 installed on the housing 400 for transmitting
an ultrasonic signal, when the ultrasonic signal contacts an
obstacle and forms an echo wave by reflection, the ultrasonic
module 300 receiving the echo signal; a control module 500
installed on the housing 400 and electrically connected to the
ultrasonic module configured to: process the echo signal of the
ultrasonic module 300 and detect an object within an detection
range of the ultrasonic module 300, and through analyzing
parameters such as a distance and strength, control a movement mode
of the movement module 600; and a cutting module 700 installed on
the housing 400 configured to cut a lawn. In particular, the
movement mode includes: keeping going straight, turning, moving
backward, slowing down, or the like. In one embodiment, when the
control module 500 determines that there is an obstacle within a
set range of the autonomous lawn mower 10 in a moving direction,
the movement module 600 is controlled to turn.
[0119] FIG. 2 is a schematic diagram of some components of an
autonomous lawn mower according to an embodiment of the present
invention. As shown in FIG. 2, a control module 500 includes a main
control board 11, an ultrasonic module 300 including an ultrasonic
probe 12, and an autonomous lawn mower 10 further including an
energy module 13. The main control board 11 is connected to the
ultrasonic probe 12 and the energy module 13 respectively.
[0120] The ultrasonic probe 12 is configured to transmit an
ultrasonic signal, receive an echo signal formed through reflection
of the ultrasonic signal by the obstacle, and transmit the echo
signal to the main control board 11.
[0121] The energy module 13 is configured to monitor a current
electric quantity of the autonomous lawn mower 10 in real time, and
send a low-energy signal to the main control board 11 when the
current electric quantity is insufficient, so that the main control
board 11 returns to a charging station according to a preset return
path.
[0122] In one embodiment, the autonomous lawn mower 10 further
includes an operating module 14, the operating module 14 being
connected to the main control board 11. The operating module 14 in
this embodiment may be a touch display apparatus, or may be a
machine-operating button, which is not specifically limited herein
in this embodiment.
[0123] In one embodiment, the autonomous lawn mower 10 further
includes a temperature sensor 15, the temperature sensor 15 being
connected to the main control board 11, and the temperature sensor
15 being configured to detect a temperature parameter of the
autonomous lawn mower 10 in a current working environment and send
the temperature parameter to the main control board 11. Those
skilled in the art may learn that a propagation speed of the
ultrasonic wave in the air varies depending on different
temperatures. A higher temperature leads to a faster propagation
speed. Control accuracy of the main control board of the autonomous
lawn mower is improved through disposing a temperature sensor on
the autonomous lawn mower.
[0124] A method for controlling an autonomous lawn mower is
provided in one embodiment of the present invention, so as to
resolve problems such as single life time being shortened and
service life of the probe being shortened as a result of frequent
enabling of an ultrasonic obstacle avoidance function, and
interference to normal working of a machine in a special working
condition. In order to make the foregoing objectives, features, and
advantages of the embodiment of the present invention more clearly
and easy to understand, the embodiment of the present invention is
described in detail below with reference to the accompanying
drawings and specific implementations.
[0125] FIG. 3 is a schematic flowchart of a method for controlling
an autonomous lawn mower according to an embodiment of the present
invention. As shown in FIG. 3, the method for controlling the
autonomous lawn mower according to this embodiment specifically
includes the following steps.
[0126] S201. A main control board receives a preset signal sent by
a signal apparatus.
[0127] The preset signal is determined by the main control board to
control enabling or disabling of an ultrasonic detection
function.
[0128] A signal apparatus in this embodiment includes any one or
more of the following: [0129] a terminal wirelessly connected to
the main control board, an ultrasonic probe, and an operating
module or an energy module of the autonomous lawn mower.
[0130] The terminal in this embodiment may be a mobile terminal,
such as a smart phone, and a tablet computer. A user performs a
corresponding operation by logging in to an application program of
the mobile terminal to implement remote control of the ultrasonic
probe of the autonomous lawn mower. The terminal in this embodiment
may also be a stationary terminal, such as a computer apparatus in
a master control room. A type of the terminal is not specifically
limited in this embodiment.
[0131] In addition, the terminal is wirelessly connected to the
main control board of the autonomous lawn mower. A connection mode
specifically includes a WIFI connection, a Bluetooth connection,
and the like. A mode of the wireless connection is not specifically
limited as long as the terminal can communicate with the main
control board of the autonomous lawn mower.
[0132] Different types of signal apparatuses correspond to
different preset signals. In one embodiment, if the signal
apparatus is a terminal or an operating module, the preset signal
is a manual control signal. If the signal apparatus is a terminal
that is wirelessly connected to the main control board, the manual
control signal is a control instruction that is sent by the
terminal and that is used to turn off the ultrasonic probe. If the
signal apparatus is the operating module, the manual control signal
is a control instruction that is sent by the operating module and
that is used to turn on or turn off the ultrasonic probe.
[0133] In one embodiment, if the signal apparatus is an ultrasonic
probe or an energy module, the preset signal is an abnormal signal,
the abnormal signal including a valid signal that satisfies a
preset condition. The valid signal may be determined using preset
strength. When an echo signal is greater than the preset strength,
the echo signal is defined as a valid signal. The valid signal may
also be determined using a distance or other parameters. When the
autonomous lawn mower can work normally and can satisfy certain
obstacle avoidance requirements, a signal that satisfies the
obstacle avoidance requirements is defined as a valid signal. The
preset condition may be that a time is greater than a preset time
or a number is greater than a preset number, etc. When the preset
condition is satisfied, the autonomous lawn mower cannot work in a
specific scenario. If the signal apparatus is the ultrasonic probe,
the abnormal signal is a valid signal that is received by the
ultrasonic probe and that satisfies the preset condition.
[0134] In one embodiment, if the signal apparatus is the ultrasonic
probe, the abnormal signal may be an echo signal indicating that a
time difference between a time at which an ultrasonic wave is
received and a time at which the ultrasonic wave is transmitted is
less than a preset time difference. If the signal apparatus is an
energy module of the autonomous lawn mower, the abnormal signal is
an energy signal that is sent by the energy module and whose energy
is less than preset energy.
[0135] In this embodiment, the operating module may be a touch
display apparatus, and the user may select turn-on or turn-off of
the ultrasonic probe through a preset touch mode on a virtual
operating interface of a touch display apparatus. A specific touch
mode includes click, double click, and slide, etc. The user may set
the touch mode according to personal preference, which is not
specifically limited in this embodiment. After the touch display
apparatus receives a touch signal, a control instruction
corresponding to the touch signal is sent to the main control board
of the autonomous lawn mower. The operating module may also be a
switch button disposed on the autonomous lawn mower, and the user
can turn on or turn off the ultrasonic probe of the autonomous lawn
mower through the switch button.
[0136] S202. The main control board generates a signal for
controlling enabling or disabling of an ultrasonic detection
function according to the preset signal.
[0137] After receiving the preset signal sent by the signal
apparatus, the main control board determines enabling or disabling
of the ultrasonic detection function of the autonomous lawn mower
according to the preset signal.
[0138] If the preset signal instructs to enable the ultrasonic
detection function, the main control board generates a switch
signal 1; or [0139] if the preset signal instructs to disable the
ultrasonic detection function, the main control board generates a
switch signal 0.
[0140] S203. The main control board enables or disables the
ultrasonic detection function according to the switch signal.
[0141] The main control board enables or disables the ultrasonic
detection function according to the switch signal 1 or 0, so that
the user or the autonomous lawn mower can automatically control
enabling or disabling of the ultrasonic detection function in a
specific working scenario. The enabling or disabling of the
ultrasonic detection function may be enabling or disabling of the
echo signal of the ultrasonic probe by the main control board, or
may be enabling or disabling of transmitting or receiving signal by
the ultrasonic probe, thereby avoiding problems such as
single-package duration being shortened and the probe service life
being shortened as a result of frequent turn-on of the ultrasonic
probe of an existing autonomous lawn mower, or interference to
normal working of the autonomous lawn mower in a special working
condition.
[0142] In one embodiment, enabling and disabling of the ultrasonic
detection function may be to disable receiving and transmitting
functions of the ultrasonic probe, such as disabling power supply
for the ultrasonic probe, or controlling the ultrasonic probe to
stop working, or may be to disable processing of the ultrasonic
signal by the control module.
[0143] An autonomous lawn mower equipped with the ultrasonic probe
determines a distance between an obstacle and the lawn mower
according to a time difference between a time at which a sound wave
signal is transmitted by the ultrasonic probe and a time at which
an echo signal is received by the ultrasonic probe. However, in
some special cases, for example, a large lump of soil adheres to a
surface of the ultrasonic probe, the sound wave signal transmitted
by the ultrasonic probe is immediately reflected by the soil on the
surface of the ultrasonic probe, and the lawn mower may mistakenly
determine that the obstacle is very close to the lawn mower and
perform a corresponding avoidance action. However, an ordinary
avoidance action for avoiding an obstacle cannot remove the soil
adhering to the surface of the probe, and the autonomous lawn mower
keeps performing the avoidance action, resulting in abnormal
working of the lawn mower or even causing damage to the lawn
mower.
[0144] According to the method for controlling the autonomous lawn
mower provided in this embodiment, the preset signal that is sent
by the signal apparatus and received by the main control board and
that is used to indicate enabling or disabling of the ultrasonic
detection function generates, according to a preset signal, the
switch signal for controlling turn-on or turn-off of the ultrasonic
probe, and turns on or turns off the ultrasonic probe according to
the switch signal. The signal apparatus includes a terminal
wirelessly connected to the main control board, the ultrasonic
probe, the operating module or the energy module of the autonomous
lawn mower. The preset signal sent by any signal apparatus can
control the ultrasonic detection function of the autonomous lawn
mower, thereby avoiding problems such as single-package duration
being shortened and the probe service life being shortened as a
result of frequent enabling of the ultrasonic obstacle-avoidance
function, and interference to normal working of the autonomous lawn
mower in a special working condition.
[0145] If the signal apparatus is an ultrasonic probe, and the
preset signal is the echo signal sent by the ultrasonic probe, the
main control board determines, according to the echo signal,
whether to turn off the ultrasonic probe of the autonomous lawn
mower. If it is determined, through analysis of the echo signal,
that the ultrasonic probe of the autonomous lawn mower is required
to be turned off, a switch signal instructing to turn off the
ultrasonic probe is generated. Therefore, the detection function of
the ultrasonic probe is automatically disabled through the main
control board of the autonomous lawn mower in a special working
condition (such as in a heavily rainy day, or an obstacle adhering
to a surface of the probe). That the signal apparatus is an
ultrasonic probe is used as an example in the following embodiments
to describe the control method in the present invention in
detail.
[0146] FIG. 4 is a schematic flowchart of a method for controlling
an autonomous lawn mower according to an embodiment of the present
invention. As shown in FIG. 4, the method for controlling the
autonomous lawn mower provided in this embodiment specifically
includes the following steps.
[0147] S301. A main control board acquires a transmission time at
which an ultrasonic probe transmits an ultrasonic signal.
[0148] It should be noted that the ultrasonic probe in this
embodiment is in a turn-on state currently, and the ultrasonic
probe periodically transmits the ultrasonic signal.
Correspondingly, the main control board acquires the transmission
time of the ultrasonic signal according to the ultrasonic signal
transmitted by the ultrasonic probe.
[0149] S302. The main control board receives an echo signal formed
through reflection of the ultrasonic signal transmitted by the
ultrasonic probe by an obstacle.
[0150] When the ultrasonic signal encounters the obstacle within a
detection range of the ultrasonic probe, the ultrasonic probe
receives the echo signal formed through reflection of the
ultrasonic signal by the obstacle. In this case, the ultrasonic
probe transmits the echo signal to the main control board.
Correspondingly, the main control board acquires a receiving time
of the echo signal according to the echo signal.
[0151] S303. The main control board acquires a distance between the
autonomous lawn mower and the obstacle according to the echo
signal.
[0152] In particular, the main control board acquires the distance
between the autonomous lawn mower and the obstacle according to the
transmission time of the ultrasonic signal, the receiving time of
the echo signal, and a propagation speed of the ultrasonic wave in
the air.
[0153] Assuming that the transmission time of the ultrasonic signal
is t_1, the receiving time of the echo signal is t_2, the
propagation speed of the ultrasonic wave in the air is c, and the
distance between the autonomous lawn mower and the obstacle is S,
then S can be obtained using the following equation I:
S=1/2(t.sub.2-t.sub.1)c Equation I
[0154] It should be noted that the propagation speed of ultrasonic
wave in the air is influenced by an ambient temperature, and the
propagation speed specifically satisfies the equation II:
c = 331.31 1 + T 273.15 Equation II ##EQU00001##
[0155] c is a propagation speed (unit: m/s) of an ultrasonic wave
in the air, and T is an ambient temperature (unit: K).
[0156] It can be seen that the propagation speed of the ultrasonic
wave in the air varies depending on different ambient temperatures.
Therefore, in order to ensure accuracy of the distance between the
autonomous lawn mower and the obstacle acquired by the main control
board, the autonomous lawn mower further includes a temperature
sensor, the temperature sensor being connected to the main control
board.
[0157] In one embodiment, before the main control board acquires
the distance between the autonomous lawn mower and the obstacle
according to the transmission time of the ultrasonic signal, the
receiving time of the echo signal, and the propagation speed of the
ultrasonic wave in the air, the method further includes: [0158]
acquiring, by the main control board, a temperature parameter of a
current environment monitored by the temperature sensor; and
determining, by the main control board, the propagation speed of
the ultrasonic wave in the air according to the temperature
parameter. The distance between the autonomous lawn mower and the
obstacle that is acquired through the foregoing steps is more
accurate.
[0159] S304. If the distance is less than a preset distance, the
main control board determines that the echo signal is used to
indicate disabling of a detection function of the ultrasonic
probe.
[0160] Those skilled in the art may understand that, in a special
working condition, for example, an obstacle adhering to the
ultrasonic probe or in a rainy day, the ultrasonic signal
transmitted by the ultrasonic probe instantly generates an echo
signal when encountering the obstacle adhering to the ultrasonic
probe or a rain curtain formed by rain drops, causing mistaken
determining of the obstacle and affecting normal operation of the
autonomous lawn mower. In order to avoid the foregoing phenomenon,
the main control board determines, according to the acquired
distance between the autonomous lawn mower and the obstacle,
whether the distance is less than the preset distance. If the
distance is less than the preset distance, the main control board
determines that the echo signal is used to indicate disabling of
the detection function of the ultrasonic probe.
[0161] The preset distance is set, so that a current working
condition or the ultrasonic probe of the autonomous lawn mower can
be monitored in real time. When it is determined that the echo
signal is abnormal, S305 and S306 are performed.
[0162] S305. The main control board generates, according to the
echo signal, a switch signal for controlling disabling of the
ultrasonic detection function.
[0163] S306. The main control board disables the ultrasonic
detection function according to the switch signal.
[0164] Implementation principles and technical effects in S305 and
S306 in this embodiment are the same as those in S202 and S203 in
the foregoing embodiments, and details are not described herein
again.
[0165] According to the foregoing embodiments, the detection
function of the ultrasonic probe is automatically disabled by the
main control board of the autonomous lawn mower in a special
working condition, to avoid affecting normal operation of the
autonomous lawn mower as result of frequent echo signals caused by
heavy rain or an obstacle adhering to the probe surface.
[0166] If the signal apparatus is the ultrasonic probe, the preset
signal is an ultrasonic signal transmitted by the ultrasonic probe,
and the main control board does not receive an echo signal of the
ultrasonic signal within a preset time period, the main control
board determines that there is no obstacle within a detectable
range of the ultrasonic probe within a certain time period, and a
switch signal indicating turn-off of the ultrasonic probe is
generated, thereby avoiding problems such as single-package
duration being shortened and the probe service life being shortened
as a result of frequent enabling of the ultrasonic
obstacle-avoidance function. The control method for the main
control board that does not receive the echo signal within the
preset time period is described in detail with reference to
specific embodiments below.
[0167] FIG. 5 is a schematic flowchart of a method for controlling
an autonomous lawn mower according to an embodiment of the present
invention. As shown in FIG. 5, the method for controlling the
autonomous lawn mower provided in this embodiment includes the
following steps.
[0168] S401. A main control board acquires a transmission time of
an ultrasonic signal transmitted by an ultrasonic probe and starts
a timer at a transmission time point.
[0169] In this embodiment, an inherent attribute of the ultrasonic
probe includes a maximum detection distance of the ultrasonic
probe. Within a range of the detection distance, a receiving time
at which the ultrasonic probe detects an echo signal at latest may
be determined according to a propagation speed of the ultrasonic
wave in the air at a normal temperature, and the main control board
sets a preset duration of the timer according to the receiving time
and a time at which the ultrasonic wave is transmitted.
[0170] The main control board starts the timer after acquiring a
transmission time of ultrasonic signal transmitted by the
ultrasonic probe. The timer is configured to indicate whether the
echo signal received by the main control board times out.
[0171] If the main control board receives the echo signal sent by
the ultrasonic probe before the timer times out, the main control
board determines that there is an obstacle within the detection
range of the ultrasonic probe. Further, the main control board
determines, according to the echo signal, that a distance between
the autonomous lawn mower and the obstacle is greater than a preset
distance, and the main control board adjusts a walking path of the
autonomous lawn mower according to the distance between the
autonomous lawn mower and the obstacle, preventing damage to an
interior of the autonomous lawn mower as a result of a collision
between the autonomous lawn mower and the obstacle.
[0172] S402. If the main control board does not receive the echo
signal sent by the ultrasonic probe after the timer times out, the
main control board determines that the ultrasonic signal is used to
indicate disabling of the detection function of the ultrasonic
probe.
[0173] If the main control board does not receive the echo signal
sent by the ultrasonic probe after the timer times out, the main
control board determines there is no obstacle within the detection
range of the ultrasonic probe, and the main control board may
automatically turn off the ultrasonic probe of the autonomous lawn
mower within a preset time period, thereby prolonging a
single-package duration of the autonomous lawn mower.
[0174] S403. The main control board generates, according to the
ultrasonic signal, a switch signal for controlling turn-off of the
ultrasonic probe.
[0175] S404. The main control board disables the ultrasonic
detection function according to the switch signal.
[0176] Implementation principles and technical effects in S403 and
S404 in this embodiment are the same as those in S202 and S203 in
the foregoing embodiments, and details are not described herein
again.
[0177] S405. The main control board acquires a disabling time at
which the ultrasonic detection function is disabled.
[0178] S406. The main control board determines a restart time
according to the disabling time, a maximal detection distance of
the ultrasonic probe, and a travelling speed of the autonomous lawn
mower.
[0179] S407. The main control board enables the ultrasonic
detection function within a preset time period before the restart
time according to the restart time.
[0180] It should be noted that, within a time period from the time
at which the main control board acquires the ultrasonic signal
transmitted by the ultrasonic probe to the time at which the main
control board turns off the ultrasonic probe after the timer times
out, the autonomous lawn mower has travelled a certain distance
along a preset path. Therefore, after the restart time is
determined, the main control board needs to turn on the ultrasonic
probe in advance within the preset time period before the restart
time, so as to prevent an obstacle from existing on the path after
the autonomous lawn mower travels the maximum detection distance of
the ultrasonic probe, and avoid a collision because it is too late
for the autonomous lawn mower to perform an avoidance action.
[0181] In the control method provided in this embodiment, if the
main control board does not receive the echo signal of the
ultrasonic signal within the preset time period, a switch signal
instructing to turn off the ultrasonic probe is generated. The
ultrasonic probe is turned off according to the switch signal, and
the ultrasonic probe is turned on within the preset time period
before the restart time is determined, to periodically turn on the
ultrasonic probe, thereby increasing the single-package duration of
the autonomous lawn mower.
[0182] If the signal apparatus is an energy module of the
autonomous lawn mower, a preset signal is a low-energy signal
transmitted by the energy module. The main control board generates
the switch signal instructing to turn off the ultrasonic probe,
thereby disabling the detection function of the ultrasonic probe
when the autonomous lawn mower is in low energy, and ensuring that
the autonomous lawn mower has enough prestored electric quantity
for returning to a charging station. A control method for the
autonomous lawn mower in a low energy working condition is
described in detail with reference to specific embodiments
below.
[0183] FIG. 6 is a schematic flowchart of a method for controlling
an autonomous lawn mower according to an embodiment of the present
invention. As shown in FIG. 6, the method for controlling the
autonomous lawn mower provided in this embodiment includes the
following steps:
[0184] S501. A main control board receives a low-energy signal sent
by an energy module, the low-energy signal being an energy signal
whose energy is less than preset energy and that is sent by the
energy module of the autonomous lawn mower.
[0185] S502. The main control board determines, according to the
low-energy signal, that the low-energy signal is used to indicate
disabling of an ultrasonic detection function.
[0186] S503. The main control board generates, according to the
low-energy signal, a switch signal for controlling disabling of the
ultrasonic detection function.
[0187] S504. The main control board disables the ultrasonic
detection function according to the switch signal.
[0188] In particular, when the main control board receives the
low-energy signal sent by the energy module of the autonomous lawn
mower, the main control determines a current position of the
autonomous lawn mower, generates a return path from the autonomous
lawn mower to the charging station, and the main control board
returns to the charging station based on the generated return path
according to a walking system for controlling the autonomous lawn
mower.
[0189] In this embodiment, when the main control board returns to
the charging station based on a determined return path after
receiving the low-energy signal sent by the energy module, if the
detection function of the ultrasonic probe is still enabled, the
main control board may mistakenly determines the charging station
as an obstacle on the return path according to an echo signal
returned by the charging station. Consequently, the autonomous lawn
mower cannot automatically return to the charging station for
charging.
[0190] According to the foregoing control method, the main control
board generates, according to the received low-energy signal, a
switch signal for indicating turn-off of the ultrasonic probe, and
turns off the ultrasonic probe according to the switch signal,
preventing a problem that the autonomous lawn mower cannot return
to the charging station for charging, and ensuring that the
autonomous lawn mower has enough prestored electric quantity to
return to the charging station.
[0191] FIG. 7 is a schematic structural diagram of a control module
of an autonomous lawn mower according to an embodiment of the
present invention. As shown in FIG. 7, a control module 60 of the
autonomous lawn mower in this embodiment includes: [0192] a
receiving module 61 configured to receive a preset signal sent by a
signal apparatus, the preset signal being used to instruct to
enable or disable a detection function of the ultrasonic probe, and
the signal apparatus including any of the following: a terminal
wirelessly connected to the main control board, an ultrasonic
probe, an operating module, or an energy module of the autonomous
lawn mower; [0193] a generating module 62 configured to generate,
according to the preset signal, a switch signal for controlling
turn-on or turn-off of the ultrasonic probe; and [0194] an
execution module 63 configured to enable or disable the detection
function of the ultrasonic probe according to the switch
signal.
[0195] The control module of the autonomous lawn mower provided in
an embodiment of the present invention may be configured to perform
the method performed by the main control board in the foregoing
method embodiment with similar implementation principles and
technical effects, and details are not described herein again.
[0196] FIG. 8 is a schematic structural diagram of a control module
of an autonomous lawn mower according to an embodiment of the
present invention. As shown in FIG. 8, if a signal apparatus is an
ultrasonic probe, a preset signal is an echo signal sent by the
ultrasonic probe. A receiving module is specifically configured to
receive an echo signal formed through reflection of an ultrasonic
signal sent by the ultrasonic probe by an obstacle.
[0197] A control module 60 further includes: an acquiring module 64
configured to acquire a distance between the autonomous lawn mower
and the obstacle according to the echo signal; and [0198] a
determining module 65 configured to determine that the echo signal
is used to indicate disabling of a detection function of the
ultrasonic probe if the distance is less than a preset
distance.
[0199] In one embodiment, the acquiring module 64 is further
configured to acquire a transmission time at which the ultrasonic
probe transmits an ultrasonic signal; and [0200] acquire a distance
between the autonomous lawn mower and an obstacle according to the
transmission time, a receiving time of an echo signal, and a
propagation speed of an ultrasonic wave in the air.
[0201] In one embodiment, the autonomous lawn mower further
includes a temperature sensor, the temperature sensor being
connected to the main control board. The acquiring module 64 is
further configured to: [0202] acquire a temperature parameter of a
current environment monitored by the temperature sensor.
[0203] The determining module 65 is further configured to determine
the propagation speed of the ultrasonic wave in the air according
to the temperature parameter.
[0204] In one embodiment, if the signal apparatus is the ultrasonic
probe, the preset signal is an ultrasonic signal transmitted by the
ultrasonic probe. The acquiring module 64 is specifically
configured to: [0205] acquire a transmission time of the ultrasonic
signal transmitted by the ultrasonic probe.
[0206] The execution module 63 is further configured to start a
timer at a transmission time point.
[0207] The determining module 65 is further configured to determine
that the ultrasonic signal is used to indicate disabling of the
detection function of the ultrasonic probe if the main control
board does not receive the echo signal sent by the ultrasonic probe
after the timer times out.
[0208] In one embodiment, the acquiring module 64 is further
configured to acquire a turn-off time at which the ultrasonic probe
is turned off.
[0209] The determining module 65 is further configured to determine
a restart time according to the turn-off time, a maximum detection
distance of the ultrasonic probe, and a travelling speed of the
autonomous lawn mower.
[0210] The performing module 63 is further configured to turn on
the ultrasonic probe within a preset time period before the restart
time according to the restart time.
[0211] In one embodiment, a signal apparatus is an energy module of
the autonomous lawn mower, and a preset signal is a low-energy
signal sent by the energy module. The acquiring module 64 is
specifically configured to: [0212] acquire the low-energy signal
sent by the energy module, the low-energy signal being a signal
sent by the energy module when a current electric quantity of the
autonomous lawn mower is less than a preset electric quantity.
[0213] The determining module 65 is further configured to
determine, according to the low-energy signal, that the low-energy
signal is configured to indicate disabling of the detection
function of the ultrasonic probe.
[0214] The control module of the autonomous lawn mower provided in
an embodiment of the present invention may be configured to perform
the method performed by the main control board in the foregoing
method embodiment with similar implementation principles and
technical effects, and details are not described herein again.
[0215] FIG. 9 is a flowchart of a method for controlling an
autonomous lawn mower according to an embodiment of the present
invention. As shown in FIG. 9, the method for controlling the
autonomous lawn mower provided in this embodiment may include the
following steps.
[0216] Step S511: An ultrasonic signal is transmitted through an
ultrasonic probe.
[0217] The ultrasonic probe of the autonomous lawn mower equipped
with an ultrasonic obstacle-avoidance system periodically transmits
the ultrasonic signal under the control of a main control
board.
[0218] Step S512: An echo signal is received through the ultrasonic
probe, the echo signal being formed through reflection of the
ultrasonic signal.
[0219] When the ultrasonic signal encounters an obstacle within a
detection range of the ultrasonic probe, the ultrasonic probe
receives the echo signal formed through reflection of the
ultrasonic signal by the obstacle. A distance between the obstacle
and the autonomous lawn mower may be determined according to the
transmitted ultrasonic signal and the received echo signal. When
the distance between the obstacle and the autonomous lawn mower is
less than a preset distance, for example, is less than 15 cm, an
avoidance operation may be performed to avoid the obstacle,
preventing negative effects caused by a collision between the
autonomous lawn mower and the obstacle.
[0220] In particular, the distance between the autonomous lawn
mower and the obstacle may be determined according to a
transmission time of the ultrasonic signal, a receiving time of the
echo signal, and a propagation speed of the ultrasonic wave in the
air.
[0221] In a possible condition, when there are some tall weeds or
weeds with relatively large branch diameters in a lawn, such as
dandelions, the autonomous lawn mower may also determine the weeds
as obstacles, and performs an avoidance operation when the distance
is less than the preset distance. However, in this case, there is
no need to perform the avoidance operation. Therefore, in order to
reduce unnecessary avoidance and improve obstacle avoidance
efficiency, after it is determined that the distance between the
obstacle and the autonomous lawn mower is less than the preset
distance, strength of the received echo signal is further
determined. The avoidance operation is performed to avoid the
obstacle only when the strength of the echo signal is greater than
preset strength. An echo signal formed through reflection by weeds
is generally relatively weak, and an echo signal formed through
reflection by obstacles such as a large stump and a stone sculpture
that really need to be avoided are relatively strong. Therefore,
increased determinations as to strength of the echo signal can
improve obstacle avoidance efficiency of the autonomous lawn
mower.
[0222] The autonomous lawn mower performs the avoidance operation
in many alternative ways such as through moving backward, turning,
bypassing, or replanning a travelling path, which is not specially
limited in this embodiment.
[0223] Step S513: After the avoidance operation is performed
according to the ultrasonic signal and the echo signal, if a number
of valid signals in echo signals received within a preset time is
greater than a preset threshold, or a time at which the valid
signals are received is greater than a preset time, an action of
terminating the avoidance operation is performed, the valid signals
being used as echo signals for the autonomous lawn mower to perform
the avoidance operation.
[0224] In some special working conditions, for example, when a
large lump of soil adheres to the ultrasonic probe or in a heavily
rainy day, the ultrasonic signal transmitted by the ultrasonic
probe is instantly reflected when encountering the large lump of
soil adhering to the ultrasonic probe or a rain curtain formed by
rain drops, and the autonomous lawn mower may mistakenly determine
that the obstacle is very close to the autonomous lawn mower and
performs a corresponding avoidance action. The autonomous lawn
mower continually receives an echo signal formed through reflection
by the soil or the rain curtain, thereby continually performing the
avoidance action. Consequently, the autonomous lawn mower cannot
work normally, for example, the autonomous lawn mower spins in situ
as a result of continual avoidance, even causing damage to the
machine. Similarly, if a user does not mow for a long time because
of going out, etc., and heights of tall grass within a working area
of the autonomous lawn mower within a detection range of the
ultrasonic probe, the autonomous lawn mower may continuously detect
an echo signal formed through reflection by the tall grass, thereby
continually performing the avoidance action and consequently, the
autonomous lawn mower cannot work normally. That is, in a special
working condition, the autonomous lawn mower may continually
receive an echo signal of high strength and continually perform the
avoidance operation, and therefore the autonomous lawn mower cannot
work normally and becomes abnormal.
[0225] In this embodiment, in order to prevent the foregoing cases
from occurring, a number of valid signals received within the
preset time is counted, or a time at which the valid signals are
received is counted. Signal strength of the valid signals is
greater than the preset strength. The valid signals may be used to
determine a relationship between a distance from an obstacle to the
autonomous lawn mower and the preset distance. The autonomous lawn
mower may be controlled, according to the valid signals, to perform
or not to perform the avoidance operation.
[0226] If the number of the valid signals received within the
preset time is greater than the preset threshold, or the time at
which the valid signals are received is greater than the preset
time, an action of terminating the avoidance operation is performed
to terminate unnecessary avoidance in time. When the autonomous
lawn mower works normally, the autonomous lawn mower successfully
avoids an obstacle after receiving a valid signal and performing an
obstacle operation, and then will not receive the valid signal.
When a large lump of soil adheres to the ultrasonic probe, the
autonomous lawn mower receives the valid signal and performs the
avoidance operation. However, the avoidance operation for avoiding
an obstacle cannot be used to avoid an obstacle in a special
working condition. Therefore, even though the avoidance operation
is performed, the autonomous lawn mower still receives a valid echo
signal, continues to perform the avoidance operation, then becomes
abnormal, and cannot work normally. Through counting the number of
valid signals received within the preset time or through counting
the time at which the valid signals are received, it may be
determined whether an abnormal condition occurs.
[0227] It should be noted that the preset time and the preset
threshold in this embodiment need to be set according to an actual
situation, and values required to be set may vary depending on
different models of the autonomous lawn mower. When the preset time
and the preset threshold are determined, a frequency at which the
ultrasonic probe of the autonomous lawn mower transmits an
ultrasonic wave and the time required by the autonomous lawn mower
to perform the avoidance operation need to be considered.
[0228] The avoidance operation can be terminated in many
alternative ways such as disabling the ultrasonic detection
function, or disabling an avoidance system of the autonomous lawn
mower, which is not limited in this embodiment.
[0229] According to the method for controlling the autonomous lawn
mower provided in this embodiment, an echo signal formed through
reflection of the ultrasonic signal transmitted by the ultrasonic
probe is received, and it is determined, according to the
transmitted ultrasonic signal and the echo signal, whether to
perform the avoidance operation, so that the autonomous lawn mower
can avoid the obstacle effectively, and determines whether a number
of valid signals received within the preset time is greater than
the preset threshold. When the number of valid signals is greater
than the preset threshold, the action of terminating the avoidance
operation is performed, thereby terminating unnecessary avoidance
in time and improving stability and reliability of the autonomous
lawn mower during working.
[0230] In one embodiment, the disabling the ultrasonic detection
function may include: disabling the detection function of the
ultrasonic probe.
[0231] In one embodiment, the disabling the ultrasonic detection
function may also include: disconnecting a power supply switch of
the ultrasonic probe without supplying power to the ultrasonic
probe. In this case, due to neither transmitting a signal nor
receiving a signal, the ultrasonic probe will not receive a valid
signal, and the autonomous lawn mower does not perform the
avoidance operation and returns to be a normal working state. Such
method may further be used to reduce power consumption of the
autonomous lawn mower and prolong service life of the ultrasonic
probe.
[0232] In one embodiment, the disabling the ultrasonic detection
function may also include: not responding to the valid signal
received by the ultrasonic probe. In other words, if the number of
valid signals received within the preset time is greater than the
preset threshold, or a time at which the valid signals are received
is greater than the preset time, even though the valid signals are
received, the echo signal is not be further processed or
analyzed.
[0233] It should be noted that after the avoidance operation is
terminated in a manner of disabling the detection function of the
ultrasonic probe provided in this embodiment, the autonomous lawn
mower may further continue mowing. In one embodiment, a mechanical
obstacle-avoidance system may be further used to avoid an
obstacle.
[0234] In one embodiment, the performing the action of terminating
the avoidance operation may include: disabling a walking system for
the autonomous lawn mower to move forward, move backward, or turn
in the autonomous lawn mower. Because the autonomous lawn mower
performs the avoidance operation depending on its walking system,
the avoidance operation cannot be naturally performed after the
walking system is disabled. Therefore, failures such as shutdown
and damage to the walking system due to continually performing the
avoidance operation are prevented.
[0235] The autonomous lawn mower is generally used outdoors with a
complex and changeable working environment. For example, the lawn
after the rain is wet and slippery, some lawns have steep slopes,
and some lawns are not flat enough with pits. For example, if there
is an obstacle that needs to be avoided within a range over which a
distance from the obstacle to the autonomous lawn mower is less
than a preset distance, the autonomous lawn mower performs an
avoidance operation after receiving a valid signal. However,
slipping may be caused in the walking system due to slippery, or
the autonomous lawn mower fails to perform the avoidance operation
as a result of being caught into the potholes in the lawn. In this
case, the autonomous lawn mower may also continually receive valid
echo signals, that is, the number of valid signals received within
the preset time may be greater than the preset threshold. In this
case, a cutting system of the autonomous lawn mower is always in a
working state, which may bring some unexpected consequences, for
example, damage to a blade in the cutting system, certain damage to
the obstacle, and the like. Therefore, in order to further improve
safety of the autonomous lawn mower during working, on the basis of
any of the foregoing embodiments, the method for controlling the
autonomous lawn mower provided in this embodiment may further
include: disabling the cutting system for cutting grass in the
autonomous lawn mower when the number of valid signals received
within the preset time is greater than the preset threshold, or
when the time at which valid signals is received is greater than
the preset time.
[0236] On the basis of any of the foregoing embodiments, the method
provided in this embodiment may further include: outputting alarm
information through a speaker and/or a indicator light if the
number of the valid signals in the echo signals received within the
preset time is greater than the preset threshold or if the time at
which valid signals are received is greater than the preset time,
the alarm information being used to indicate that the autonomous
lawn mower is abnormal.
[0237] In one embodiment, an alarm sound may be sent through the
speaker as a prompt, or preset voice information may be played
through the speaker as a prompt, for example, " , (Master, I need
help)" may be played to ask the user for help. Specific content of
the alarm sound and the voice information is not limited in this
embodiment, which may be set according to actual needs.
[0238] In one embodiment, alarm information may be further output
through an indicator light in the autonomous lawn mower, and a
specific installation position of the indicator light in the
autonomous lawn mower is not limited in this embodiment. For
example, the indicator light may be installed on an operating
interface of the autonomous lawn mower, or may be installed on a
housing of the autonomous lawn mower. Prompting may be performed
through flashing or a constantly lit indicator light. Further, an
urgency degree of a condition may also be indicated through a color
of the indicator light. For example, red represents an emergency,
and yellow represents a normal condition.
[0239] Regardless of which way is used for prompting, the purpose
is to enable the user to perform human intervention as soon as
possible and thoroughly eliminate a cause of causing an abnormal
condition.
[0240] On the basis of any of the foregoing embodiments, the method
provided in this embodiment may further include: sending prompt
information to a terminal if the number of valid signals in the
echo signals received within the preset time is greater than the
preset threshold or if the time at which the valid signals are
received is greater than the preset time, the prompt information
being used to indicate that the autonomous lawn mower is abnormal
and the terminal apparatus is connected to the autonomous lawn
mower in a wireless connection manner.
[0241] With the continuous development of the Internet of Things
technologies, a manner in which an autonomous appliance is
controller through a terminal apparatus has been widely used. In
this embodiment, the terminal apparatus may be used to control an
autonomous lawn mower, and a working state of the autonomous lawn
mower may be checked. When the autonomous lawn mower is abnormal,
prompt information may be sent to the terminal apparatus to remind
the user. The user may perform human intervention in time to
thoroughly eliminate the cause of an abnormal condition after
receiving the prompt information. For example, the user may clear
soil adhering to an ultrasonic probe away, so that the autonomous
lawn mower may restore automatic obstacle avoidance. The user may
remove the autonomous lawn mower from a pothole in a lawn to enable
the autonomous lawn mower to continue working normally.
[0242] The terminal apparatus in this embodiment may be a mobile
terminal, for example, a smart phone, a tablet computer, etc. The
terminal in this embodiment may also be a fixed terminal, for
example, a computer apparatus in a main control room. The terminal
apparatus is not specifically limited in this embodiment. In
addition, the wireless connection manner between the terminal
apparatus and the autonomous lawn mower may be a WIFI connection, a
Bluetooth connection, or a cellular mobile communication network
may be used. The wireless connection manner is not specifically
limited in this embodiment as long as the terminal apparatus can
communicate with the autonomous lawn mower.
[0243] On the basis of the foregoing embodiments, the foregoing
embodiments are combined in this embodiment. Referring to FIG. 10,
only FIG. 10 is used as an example in the embodiments of the
present invention, which does not indicate that the present
invention is not limited thereto. FIG. 10 is a flowchart of another
embodiment of a method for controlling an autonomous lawn mower
according to the present invention. As shown in FIG. 10, the method
for controlling the autonomous lawn mower provided in this
embodiment may include the following steps:
[0244] Step S611: An ultrasonic signal is transmitted through an
ultrasonic probe.
[0245] Step S612: An echo signal is received through the ultrasonic
probe, the echo signal being formed through reflection of the
ultrasonic signal.
[0246] Step S613: According to the ultrasonic signal and the echo
signal, after an avoidance operation is performed, if a number of
valid signals in echo signals received within a preset time is
greater than a preset threshold, or if a time at which the valid
signals are received is greater than a preset time, a detection
function of the ultrasonic probe is disabled, and prompt
information is sent to a terminal apparatus.
[0247] According to the method for controlling the autonomous lawn
mower provided in this embodiment, it is determined whether the
avoidance operation is performed according to the transmitted
ultrasonic signal and the echo signal, so as to effectively avoid
an obstacle and prevent a collision. When a number of valid signals
received within the preset time is greater than the preset
threshold, or when the time at which the valid signals are received
is greater than the preset time, the detection function of the
ultrasonic probe is disabled, preventing the autonomous lawn mower
from being caught in the endlessly cyclic avoidance operation, so
that the autonomous lawn mower can work normally. When the number
of the valid signals received within the preset time is greater
than the preset threshold, prompt signal is sent to the terminal
apparatus wirelessly connected to the autonomous lawn mower for
prompting, so as to remind the user of performing human
intervention to thoroughly eliminate a cause of an abnormal
condition. According to the method for controlling the autonomous
lawn mower provided in this embodiment, stability and reliability
of the autonomous lawn mower during working are improved.
[0248] A control module of an autonomous lawn mower is further
provided in an embodiment of the present invention. After an
avoidance operation is performed according to an ultrasonic signal
and an echo signal, if a number of valid signals in echo signals
received within a preset time is greater than a preset threshold,
or if a time at which the valid signals are received is greater
than a preset time, an action of terminating the avoidance
operation is performed, the valid signals being used as the echo
signals for the autonomous lawn mower to perform the avoidance
operation.
[0249] In one embodiment, the ultrasonic probe is an ultrasonic
probe that is separately transmitted or separately received, that
is, a design with transmitting separated from receiving, and a
transmitting module and a receiving module are two independent
modules. In another embodiment, the ultrasonic probe is an
ultrasonic probe integrated with transmitting and receiving.
Therefore, the transmitting module and the receiving module are
actually a same module, that is, a same module implements function
of both transmitting and receiving.
[0250] A device in this embodiment may be configured to implement
the technical solutions of the foregoing method embodiment with
similar implementation principles and technical effects, and
details are not described herein again.
[0251] In one embodiment, the control module is specifically
configured to: disable a detection function of the ultrasonic probe
to terminate an avoidance operation if a number of valid signals in
the echo signals received within a preset time is greater than a
preset threshold, or if a time at which the valid signals are
received is greater than a preset time.
[0252] In one embodiment, the control module is specifically
configured to: disable a walking system for the autonomous lawn
mower to move forward, move backward, or turn to terminate the
avoidance operation if the number of the valid signals in the echo
signals received within the preset time is greater than the preset
threshold or if the time at which the valid signals are received is
greater than the preset time.
[0253] In one embodiment, the control module is specifically
configured to: disable a cutting system for cutting grass in the
autonomous lawn mower if the number of the valid signals in the
echo signals received within the preset time is greater than the
preset threshold or if the time at which the valid signals are
received is greater than the preset time.
[0254] In one embodiment, the control module of the autonomous lawn
mower may include a prompt module. The prompt module is
specifically configured to: output alarm information through a
speaker and/or an indicator light if the number of the valid
signals in the echo signals received within the preset time is
greater than the preset threshold or if the time at which the valid
signals are received is greater than the preset time, the alarm
information being used to indicate that the autonomous lawn mower
is abnormal.
[0255] In one embodiment, the prompt module may be further
configured to: send prompt information to a terminal apparatus if
the number of the valid signals in the echo signals received within
the preset time is greater than the preset threshold or if the time
at which the valid signals are received is greater than the preset
time, the prompt information being used to indicate that the
autonomous lawn mower is abnormal, and the terminal apparatus being
connected to the autonomous lawn mower in a wireless connection
manner.
[0256] FIG. 11 is a schematic structural diagram of a control
module of an autonomous lawn mower according to an embodiment of
the present invention. As shown in FIG. 11, a control module 60 of
the autonomous lawn mower provided in this embodiment includes:
[0257] a memory 81; a processor 82; and a computer program.
[0258] The computer program is stored in the memory 81, and the
processor 82 is configured to perform the method in any of the
foregoing embodiments, to control enabling or disabling of a
detection function of an ultrasound probe.
[0259] In one embodiment, the memory 81 may be either independent,
or may be integrated with the processor 82.
[0260] When the memory 81 is a device independent of the processor
82, the control module 60 may further include: [0261] a bus 83
configured to connect the memory 81 and the processor 82.
[0262] The autonomous lawn mower has an obstacle-avoidance
function. One way is to give way using a collision sensor through a
collision between the autonomous lawn mower and an obstacle.
However, the collision may result in damage to obstacles (flowers,
bushes, etc.), and a long-term collision may cause damage to the
autonomous lawn mower. The other way is to avoid or bypass in
advance using an ultrasonic sensor to detect an obstacle such as a
tree when the autonomous lawn mower approaches the obstacle, so as
to prevent a collision with the obstacle. However, because angles
at which the ultrasonic sensor performs transmitting and receiving
in a vertical direction usually cannot cover the ground, the
ultrasonic sensor cannot recognize the obstacle having a relatively
short height.
[0263] In the embodiment of the present invention, the autonomous
lawn mower is used as an example to describe the self-moving
apparatus and the method controlling same. The automatic walking
apparatus mentioned in the embodiment may be understood as a
self-moving apparatus.
[0264] Referring to FIG. 12, in one embodiment, a method for
avoiding an obstacle by an autonomous lawn mower includes the
following steps.
[0265] S110: A first signal indicating that there is an obstacle
within a first height range is acquired.
[0266] An object defined as an obstacle can prevent the autonomous
lawn mower from walking, and therefore it is necessary to change a
walking path of the autonomous lawn mower to avoid the
obstacle.
[0267] In one embodiment, referring to FIG. 18, the autonomous lawn
mower is equipped with an ultrasonic probe, the ultrasonic probe
being provided with a transmitting device and a receiving device.
The autonomous lawn mower mows on a lawn, and the ultrasonic
transmitting device transmits an ultrasonic wave toward a
travelling direction of the autonomous lawn mower. The ultrasonic
wave propagates in the air and is instantly reflected by an
obstacle on the way, and the ultrasonic receiving device receives a
reflection wave. The reflection wave is defined as a first signal.
Because the ultrasonic wave has strong directivity and propagates a
long distance in a medium, the ultrasonic wave may be used for
distance measurement.
[0268] The ultrasonic probe is installed on a floating cover of the
autonomous lawn mower and located at a certain height from the
ground, which may be used to detect relatively big obstacles, such
as trunks and chairs. A detection range of the ultrasonic wave is a
first height (H1) range. When there is an obstacle within the first
height (H1) range, the receiving device receives, through
characteristics of the ultrasonic wave, the ultrasonic signal
reflected by the obstacle. After processing and calculation, the
autonomous lawn mower is controlled to perform an avoidance action
at a position with a certain distance from the obstacle, further
avoiding the collision between the obstacle and the autonomous lawn
mower.
[0269] S120: A second signal indicating that there is an obstacle
within a second height range is acquired.
[0270] In one embodiment, referring to FIG. 18, there is an
obstacle within a second height (H2) range in a mowing environment
of the autonomous lawn mower, for example, bushes, flowers, and the
like. For obstacles existing within the second height (H2) range
and beyond a height range detected by the ultrasonic probe, the
autonomous lawn mower is provided with a magnetic block and a Hall
element for sensing the magnetic block to detect the obstacles.
[0271] The magnetic block is fixed inside the housing of the
autonomous lawn mower. The Hall element is distributed within a
magnetic field range of the magnetic block for determining whether
the magnetic block moves by detecting a change in the magnetic
strength. A displacement signal of the magnetic block is defined as
a second signal.
[0272] In a word, after the autonomous lawn mower collides with an
obstacle within the second height range, the housing deforms to
some extent due to the collision, and the magnetic block is
displaced relative to the Hall sensor with the deformation of the
housing. The magnetic field of the magnetic block changes due to
the position change, and the Hall sensor detects the displacement
of the magnetic block, thereby detecting that the autonomous lawn
mower collides with an obstacle, and further controlling the
autonomous lawn mower to turn or move backward.
[0273] S200: An obstacle-avoidance instruction is issued according
to the first signal and the second signal.
[0274] The ultrasonic signal reflected by the obstacle within the
first height range is defined as the first signal in the foregoing
description. The autonomous lawn mower collides with the obstacle
within the second height range, the magnetic block disposed on the
housing of the autonomous lawn mower is displaced, and a
displacement signal is the second signal.
[0275] Further, a minimum value within the first height range is
set to be not greater than a maximum value within a second height
range, and there is no gap and there is even an overlapping portion
between the first height range and the second height range. Then,
in a working environment of the autonomous lawn mower, a height of
an obstacle substantially covers the first height range and the
second height range. Within the first height range covered by the
ultrasonic wave, the obstacle is detected using characteristics of
the ultrasonic wave, and the first signal is acquired. At a
location with a certain distance from the obstacle, the autonomous
lawn mower is controlled to perform an avoidance action. Within the
second range that the ultrasonic wave cannot cover, the obstacle is
detected through collision contact, the second signal is acquired,
and the autonomous lawn mower is controlled to turn or move
backward. In this way, obstacles within different height ranges may
be detected using the foregoing obstacle avoidance methods, and
different obstacle avoidance means may be further used.
[0276] In summary, according to the first signal and the second
signal, two obstacle avoidance means are combined to detect
obstacles within different height ranges and determine whether the
autonomous lawn mower encounters the obstacle. When working in a
complex environment such as flowers, trunks, and bushes, the
autonomous lawn mower performs the avoidance action to be adapted
to the complex working environment, and safety of the autonomous
lawn mower is improved.
[0277] S300: A walking path of the autonomous lawn mower is changed
according to an obstacle-avoidance instruction.
[0278] According to the first signal and the second signal, the
autonomous lawn mower issues the obstacle avoidance instruction to
control movement of the autonomous lawn mower. For example, at a
location with a certain distance from the autonomous lawn mower,
there is an obstacle within the first height (H1) range, a
transmission signal of the ultrasonic wave is detected, and an
obstacle-avoidance instruction for turning is issued to control the
autonomous lawn mower to turn.
[0279] Further, referring to FIG. 13, in one embodiment, a method
for avoiding an obstacle by an autonomous lawn mower further
includes the following steps:
[0280] S111: An ultrasonic signal is sent to a surrounding
environment.
[0281] S112: A reflection signal of an ultrasonic signal is
received from the surround environment.
[0282] S113: It is determined, according to the reflection signal,
whether there is an obstacle within a first height range is
determined.
[0283] Further, in one embodiment, the step of the determining
whether there is an obstacle within a first height range
specifically includes: [0284] acquiring a first preset parameter
value indicating that there is an obstacle within the first height
range; and [0285] determining that there is an obstacle within the
first height range when a first parameter value of the reflection
signal is greater than the first preset parameter value indicating
that there is an obstacle within the first height range.
[0286] The first parameter value of the reflection signal is a
strength value of the reflection signal.
[0287] Further, in one embodiment, the step of acquiring a first
signal indicating that there is an obstacle within the first height
range further includes:
[0288] S114: A time difference between a moment at which the
ultrasonic wave is transmitted and a moment at which the ultrasonic
wave is received is converted into a second parameter value of the
first signal, the second parameter value of the first signal being
used to represent a distance between the autonomous lawn mower and
both obstacles within the first height range.
[0289] In particular, an ultrasonic transmitting device transmits
an ultrasonic wave toward a direction, the ultrasonic wave
propagating in the air and returning instantly when colliding with
an obstacle during propagation. An ultrasonic receiving device
receives an ultrasonic wave that is reflected, calculates signal
strength of the ultrasonic wave that is reflected, and acquires a
preset signal strength value of the ultrasonic wave that is
reflected. When a reflected ultrasonic signal strength value is
greater than a preset ultrasonic signal strength value, it is
determined that there is an obstacle within the first height
range.
[0290] Further, timing is started at the same moment at which the
ultrasonic wave is transmitted, and the ultrasonic receiving device
stops timing immediately after receiving the reflected ultrasonic
wave. That is, a timer records a time difference T between the
moment at which the ultrasonic wave is transmitted and the moment
at which the ultrasonic wave is received. The time difference T is
defined as a first signal parameter value representing a distance
between an autonomous walking apparatus and an obstacle.
[0291] Within a time period between the moment at which the
ultrasonic wave is transmitted and the moment at which the
ultrasonic wave is received, the ultrasonic wave moves back and
forth between the obstacle and the autonomous lawn mower. A
propagation speed of the ultrasonic wave in the air is denoted as
V. According to the time T recorded by the timer, a distance S
between a transmitting device and an obstacle may be calculated,
that is, S=V*T/2.
[0292] Referring to FIG. 13, in one embodiment, a method for
avoiding an obstacle by an autonomous lawn mower further includes
the following steps:
[0293] S211: A second preset parameter value of a first signal is
acquired.
[0294] S212: When a second parameter value of the first signal is
less than the second preset parameter value of the first signal, an
obstacle-avoidance instruction is issued.
[0295] In particular, in order to set the second preset parameter
value of the first signal, the second preset parameter value of the
first signal may be directly implanted into a control program and
is directly invoked when the program is executed. Alternatively,
the second preset parameter value of the first signal that is
directly input by the outside is received and is further stored in
a memory. The second preset parameter value of the first signal in
the memory is invoked when the program is executed. The second
preset parameter value of the first signal may be a time parameter,
or may be a distance parameter.
[0296] When the second preset parameter of the first signal is the
time parameter, the first signal parameter value T is compared to a
preset time parameter. When the first signal parameter value T
exceeds the preset time, an obstacle-avoidance instruction is
issued.
[0297] When the second preset parameter of the first signal is the
distance parameter, because the propagation speed of the ultrasonic
wave in the air is about 340 m/s, the distance parameter may be
converted into the time parameter. The first signal parameter value
T is compared to the converted time parameter. When the first
signal parameter value T exceeds the preset time, an
obstacle-avoidance instruction is issued.
[0298] The autonomous lawn mower is installed with an ultrasonic
probe. At a position with a certain distance from an obstacle, the
autonomous lawn mower performs an avoidance action against the
obstacle to avoid a collision with the obstacle, further preventing
damage to the obstacle and the autonomous lawn mower as a result of
the collision.
[0299] Further, referring to FIG. 14, in another embodiment, a
method for avoiding an obstacle by an autonomous lawn mower further
includes the following steps:
[0300] S121: The autonomous lawn mower collides with an obstacle
within a second height range.
[0301] S122: A second signal parameter value indicating that there
is an obstacle within the second height range is acquired.
[0302] The autonomous lawn mower encounters obstacles such as
flowers and bushes within the second height range when mowing, such
obstacles being beyond a detection area of the ultrasonic wave. The
autonomous lawn mower inevitably collides with the obstacles within
the second height range.
[0303] Deformation of a housing of the autonomous lawn mower is
detected using a magnetic block and a Hall element, and it is
further determined whether a collision occurs to the autonomous
lawn mower. The magnetic block is fixed to the housing of the
autonomous lawn mower, and the Hall element is distributed within a
range of the magnetic field of the magnetic block.
[0304] When the autonomous lawn mower collides with an obstacle,
the housing is deformed. The magnetic block is displaced relative
to the Hall sensor with the deformation of the housing, the
magnetic field changes due to a change in a position of the
magnetic block, and the Hall element may be used to detect the
displacement of the magnetic block. The Hall element converts the
detected physical quantity of the displacement into an electric
quantity, thereby controlling the autonomous lawn mower. An
electric quantity signal output by the Hall element is defined as
the second signal parameter value.
[0305] S221: A preset parameter value of a second signal is
acquired.
[0306] S222: When the second signal parameter value is greater than
a preset parameter value of the second signal, an obstacle
avoidance instruction is issued.
[0307] In particular, in order to set the preset parameter value of
the second signal, the preset parameter value of the second signal
may be directly implanted into a control program and, and is
directly invoked when the program is executed. Alternatively, the
preset parameter value of the second signal directly input by the
outside is received and further stored in a memory, and the preset
parameter value of the second signal in the memory is invoked when
the program is executed. The second signal parameter value is an
electric quantity parameter.
[0308] The second signal parameter value is compared to the preset
electric quantity parameter of the second signal. When the second
signal parameter value is greater than the preset electric quantity
parameter value of the second signal, an obstacle-avoidance command
is issued.
[0309] For an obstacle beyond the ultrasonic detection area, the
Hall element is configured to detect the displacement of the
magnetic block, thereby detecting that the autonomous lawn mower
collides with an obstacle, and further controlling the autonomous
lawn mower to turn and move backward to reduce damage to the
obstacle.
[0310] In the method for avoiding the obstacle by the autonomous
lawn mower, two sensors including the ultrasonic probe and the Hall
element are jointly used to detect obstacles within different
height ranges. When working in a complex environment with flowers,
trunks, and bushes, etc., the autonomous lawn mower uses the
obstacle avoidance method to perform an avoidance action, which is
more intelligent to be adapted to the complex working environment,
and safety of the autonomous lawn mower is improved.
[0311] In one embodiment, an obstacle-avoidance system of the
autonomous lawn mower specifically includes: [0312] a first
detecting module configured to acquire a first signal indicating
that there is an obstacle within a first height (H1) range; [0313]
a second detecting module disposed below the first detecting module
configured to acquire a second signal indicating that there is an
obstacle within a second height (H2) range; [0314] a processing
module configured to issue an obstacle-avoidance instruction
according to the first signal and the second signal; and [0315] a
control module configured to control a walking path of the
autonomous lawn mower according to the obstacle-avoidance
instruction.
[0316] Further, the first detecting module includes an ultrasonic
probe. The ultrasonic probe is configured to transmit and receive
an ultrasonic signal. The ultrasonic probe is installed on a fixing
base of the ultrasonic probe, the fixing base of the ultrasonic
probe being disposed on a top of the housing of the autonomous lawn
mower. A second detecting module includes a magnetic block and a
Hall element for inducing the magnetic block. The Hall element is
configured to detect whether the magnetic block is displaced. The
Hall element includes at least two Hall sensors.
[0317] In one embodiment, the obstacle-avoidance system of the
autonomous lawn mower specifically includes: an ultrasonic module
and an auxiliary detecting module. As shown in FIG. 15, the
autonomous lawn mower 10 includes a housing 400, a movement module
600 including a driving wheel 100 and a driven wheel 200, a cutting
module 700, an ultrasonic module 300, and an auxiliary detecting
module 410, etc. The driving wheel 100 supports the housing 400,
which is subject to forward ground friction force to provide a
driving force for the autonomous lawn mower 10 to travel. The
driven wheel 200 supports the housing 400 and travels with the body
of the driving wheel 100, and the driven wheel 200 may be rotatable
within a predetermined angle range. The ultrasonic module 300
includes an ultrasonic probe 12. Referring to FIG. 16 and FIG. 17,
the autonomous lawn mower 10 is provided with two fixing bases 310
of the ultrasonic probe, which are respectively installed on left
and right sides of the housing 400. The ultrasonic probe 12 is
installed on the fixing base 310 of the ultrasonic probe. Lateral
coverage of the ultrasonic probe is 110%, and a recognition
distance of the ultrasonic probe is 5-95 mm. In this embodiment,
the auxiliary detecting module 410 may be a non-contact detecting
module, such as the ultrasonic module, or may be a contact
detecting module, such as the Hall element.
[0318] In one embodiment, an angle between an ultrasonic axis and
an central axis of the autonomous lawn mower ranges from 30.degree.
to 50.degree., and a horizontal distance between a front end of the
fixing base of the ultrasonic probe and a front end of the housing
ranges from 110 mm to 130 mm. An installation position of the
ultrasonic probe determines that the angle between the ultrasonic
axis and the central axis of the autonomous lawn mower is
38.degree., so that the ultrasonic wave can detect an obstacle on
one side of the autonomous lawn mower, and has a wide detection
area in a horizontal direction. A horizontal distance between the
front end of the fixing base of the ultrasonic probe and the front
end of the housing is 126.4 mm. Therefore, the autonomous lawn
mower has no blind area.
[0319] The foregoing autonomous lawn mower may detect obstacles
within different height ranges. When working in a complex
environment with flowers, trunks, and bushes, the autonomous lawn
mower performs an avoidance action, which is more intelligent to be
adapted to the complex working environment, and safety of the
autonomous lawn mower is improved.
[0320] A specific application scenario of an embodiment of the
present invention is described below with reference to FIG. 18.
[0321] There are obstacles such as trunks, flowers, bushes, and
chairs on a lawn. These obstacles vary in height, for example,
heights of the flowers and bushes are lower than a height of the
lawn mower, and heights of the trunks and chairs are higher than
the height of the lawn mower. The obstacle-avoidance system of the
lawn mower provided in the present invention includes an ultrasonic
probe and a Hall element.
[0322] The ultrasonic probe is installed on a top of the housing of
the autonomous lawn mower. There are at least two ultrasonic
probes, so that the lateral coverage of the ultrasonic probe is
110%. The ultrasonic probe detects an obstacle with a relatively
high height, such as trunks, and a height at which the ultrasonic
probe performs detecting is denoted as H1. When there is an
obstacle within the first height (H1) range, the ultrasonic wave is
reflected by the obstacle, and the ultrasonic probe receives an
ultrasonic signal reflected by the obstacle. Through processing and
calculation, a distance between the obstacle and the autonomous
lawn mower is obtained. Because the propagation speed of the
ultrasonic wave in the air is 340 m/s, a distance parameter may
also be converted into a time parameter. A preset parameter value
is acquired, and the time parameter or the distance parameter
obtained through processing is compared to the preset time
parameter or distance. When the parameter value obtained through
processing exceeds the preset parameter value, an
obstacle-avoidance instruction is issued. The autonomous lawn mower
changes the walking path, such as turning, according to the
obstacle-avoidance instruction. Therefore, the autonomous lawn
mower may be controlled to perform an avoidance action using the
ultrasonic probe at a position with a certain distance from an
obstacle, preventing a collision between the obstacle and the
autonomous lawn mower.
[0323] A distance from a bottom of the autonomous lawn mower to the
ground is 60 mm, so that the autonomous lawn mower may pass
smoothly when encountering an obstacle with a height less than 60
mm. When the obstacle is higher than 60 mm and is located within
the height H2 range, the obstacle cannot be covered by the
ultrasonic detection area, and such obstacle may be avoided using
the magnetic block and the Hall element. The magnetic block is
fixed on the housing of the autonomous lawn mower. The Hall element
is distributed within a magnetic field range of the magnetic block
for determining whether the magnetic block moves by detecting a
change in the magnetic strength. When the autonomous lawn mower
collides with an obstacle within the second height (H2) range, the
housing deforms due to the collision, and the magnetic block is
displaced to some extent relative to the Hall sensor with the
deformation of the housing. The Hall sensor detects displacement of
the magnetic block and further detects that the autonomous lawn
mower collides with an obstacle, further controlling the autonomous
lawn mower to avoid the obstacle, for example, moving backward.
[0324] The autonomous lawn mower and a method for avoiding the
obstacle thereby provided in one embodiment of the present
invention are used to detect obstacles within different height
ranges. When working in a complex environment with flowers, trunks,
and bushes, the autonomous lawn mower performs an avoidance action,
which is more autonomous to be adapted to the complex working
environment, and safety of the autonomous lawn mower is
improved.
[0325] The above embodiments are merely intended for describing the
technical solutions of the present invention rather than limiting
the present invention. Although the present invention has been
described in detail with reference to the foregoing embodiments,
persons of ordinary skill in the art should understand that they
may still make modifications to the technical solutions recorded in
the foregoing embodiments or make equivalent substitutions to some
technical features thereof, as long as such modifications or
substitutions do not cause the essence of corresponding technical
solutions to depart from the scope of the technical solutions of
the embodiments of the present invention.
* * * * *